Add row, col, has_index, has_element builtins
Add row, col, has_index, has_element builtins

jjdekker/libminizinc,nathanielbaxter/libminizinc,nathanielbaxter/libminizinc,jjdekker/libminizinc,jjdekker/libminizinc,tias/libminizinc,nathanielbaxter/libminizinc,tias/libminizinc,nathanielbaxter/libminizinc,jjdekker/libminizinc